Author: Robert Hyatt
Date: 10:41:31 02/28/01
Go up one level in this thread
On February 28, 2001 at 12:19:42, Uri Blass wrote: >On February 28, 2001 at 11:46:37, Enrique Irazoqui wrote: > >>On February 28, 2001 at 10:54:13, Uri Blass wrote: >> >>>On February 28, 2001 at 09:57:06, Enrique Irazoqui wrote: >>> >>>>On February 28, 2001 at 07:21:44, Jeremiah Penery wrote: >>>> >>>>>On February 27, 2001 at 13:35:33, Enrique Irazoqui wrote: >>>>> >>>>>>On February 27, 2001 at 10:49:29, Uri Blass wrote: >>>>>> >>>>>>>On February 27, 2001 at 10:07:31, Robert Hyatt wrote: >>>>>>> >>>>>>>>On February 27, 2001 at 08:24:14, Jorge Pichard wrote: >>>>>>>> >>>>>>>>>I believe that the drawish move was Qe3! instead of the Qxc6? Can somebody >>>>>>>>>post the FEN string that produce the graphical position for me. Plus I wonder >>>>>>>>>what program save the draw in the shortest time possible? >>>>>>>> >>>>>>>> >>>>>>>>None can see this. It is a 60+ ply repetition. Way beyond anything we can >>>>>>>>see today. >>>>>>> >>>>>>>We need to test all the programs in order to say that none can see it. >>>>>>> >>>>>>>Some programs like dark thought are not available so we cannot know that none >>>>>>>can see it. >>>>>>> >>>>>>>The fact that it is 60 ply repetition is not a proof that none can see it >>>>>>>because programs only to need the right extensions to see the relevant 60 plies >>>>>>>forward. >>>>>>> >>>>>>>If you are wrong then testing only one program is enough to prove it. >>>>>>> >>>>>>>Uri >>>>>> >>>>>>Deep Fritz doesn't see the draw yet after one hour, but it's getting there. Now >>>>>>I am trying with Deep Shredder and I might leave one of them computing the >>>>>>position overnight. >>>>>> >>>>>>What has been the evaluation that came closest to 0.00? >>>>>> >>>>>>Enrique >>>>>> >>>>>>Comp Deep Blue - Kasparov,G >>>>>>1r6/5kp1/RqQb1p1p/1p1PpP2/1Pp1B3/2P4P/6P1/5K2 b - - 0 1 >>>>>> >>>>>>Analysis by DEEP FRITZ : >>>>>> >>>>><SNIP> >>>>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Kg1 >>>>>> ± (1.00) Depth: 19/50 00:25:38 1907813kN >>>>>>45...Qe3! >>>>>> ² (0.69) Depth: 20/52 00:56:36 4195172kN >>>>>> >>>>>>(Irazoqui, Cadaqués 27.02.2001) >>>>> >>>>>I have let various versions of Crafty search this position for very long periods >>>>>of time in the past. I've had it return what looks like a draw score at around >>>>>ply 21 or so, and then at the next ply the score will go back up and the line >>>>>will change a lot! I never could figure out why this was. >>>>> >>>>>BTW, there is a good line posted at the bottom of http://www.rebel.nl/db2.htm >>>>>for this position. It looks like Fritz is following it fairly well so far, but >>>>>Crafty also looked to be following it when it found the drawscore, then it >>>>>changed its mind away from the line, and again the score started to rise. :( >>>> >>>>Same thing with Deep Fritz. What I find surprising is that Deep Blue expected >>>>46... Qxc6, when Deep Fritz, Deep Shredder beta and Junior 7 beta, for instance, >>>>pick Qe3 very quickly. >>>> >>>>Enrique >>>> >>>> >>>>Comp Deep Blue - Kasparov,G >>>>1r6/5kp1/RqQb1p1p/1p1PpP2/1Pp1B3/2P4P/6P1/5K2 b - - 0 1 >>>> >>>>Analysis by DEEP FRITZ : >>>> >>>>45...Qxc6 >>>> ± (0.91) Depth: 1/6 00:00:00 >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Be7 47.Bd5+ Ke8 48.c7 Rc8 49.Ra7 >>>> ± (1.16) Depth: 6/15 00:00:00 10kN >>>>45...Qxc6 46.dxc6 Bc7 47.Ra7 Rc8 48.Rb7 Ke7 49.Rxb5 >>>> ± (1.37) Depth: 7/16 00:00:00 31kN >>>>45...Qxc6 46.dxc6 Bc7 47.Ra7 Rc8 48.Rb7 Ke7 49.Ke2 Kd6 50.Rxb5 >>>> +- (1.44) Depth: 8/17 00:00:00 65kN >>>>45...Qxc6 46.dxc6 Bc7 47.Ra7 Rc8 48.Rb7 Ke7 49.Ke2 Kd6 50.Rxb5 >>>> +- (1.44) Depth: 9/19 00:00:00 115kN >>>>45...Qxc6 46.dxc6 Kf8 47.Ra7 Rc8 48.Rb7 Ra8 49.Rxb5 Ra3 50.Rd5 Ke7 >>>> +- (1.53) Depth: 10/22 00:00:00 305kN >>>>45...Qxc6 46.dxc6 Kf8 47.Ra7 Rc8 48.Rb7 Rc7 49.Rxb5 Ke7 >>>> +- (1.56) Depth: 11/21 00:00:00 1078kN >>>>45...Qxc6 46.dxc6 Kf8 47.Ra7 Rc8 48.Rb7 Rc7 49.Rxb5 Ke7 >>>> +- (1.56) Depth: 12/22 00:00:01 1597kN >>>>45...Qxc6 46.dxc6 Rc8 47.Ra5 Ke7 48.Rxb5 h5 49.Bd5 Rb8 50.Rxb8 Bxb8 >>>> +- (1.78) Depth: 13/26 00:00:02 3199kN >>>>45...Qxc6 46.dxc6 Rc8 47.Ra5 h5 48.Rxb5 h4 49.Rb7+ Rc7 50.Bd5+ Ke7 51.Bxc4 >>>> +- (1.84) Depth: 14/26 00:00:06 6898kN >>>>45...Qe3! >>>> +- (1.81) Depth: 14/39 00:00:21 25200kN >>>>45...Qe3! 46.Qd7+ Kg8 47.Qxd6 Rf8 48.Qe6+ Kh7 49.Qe7 Rg8 50.Bf3 Qc1+ 51.Kf2 >>>> ± (1.22) Depth: 14/39 00:00:29 34959kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 Re7 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Kg3 Qe1+ 51.Kh3 >>>> ± (1.16) Depth: 15/39 00:00:58 71272kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Kg1 >>>> ± (1.28) Depth: 16/43 00:01:48 133552kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Bf3 >>>> ± (1.28) Depth: 17/45 00:04:03 301257kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Bf3 >>>> ± (1.28) Depth: 18/46 00:09:44 723368kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Kg1 >>>> ± (1.06) Depth: 19/50 00:22:41 1678502kN >>>>45...Qe3 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Kg1 >>>> ± (1.00) Depth: 20/49 01:04:45 4818191kN >>>>45...Qe3! >>>> ² (0.69) Depth: 21/54 02:32:36 11295715kN >>>>45...Qe3! 46.Qxd6 Re8 47.h4 h5 48.Bf3 Qc1+ 49.Kf2 Qd2+ 50.Be2 Qf4+ 51.Kg1 >>>> ² (0.31) Depth: 21/54 04:29:02 19961605kN >>>>45...Qe3 46.Qxd6 Re8 47.Qd7+ Re7 48.Qc6 Qxe4 49.d6 Qxf5+ 50.Kg1 Rd7 51.Qxb5 >>>> ² (0.31) Depth: 22/57 09:15:31 41587594kN >>>>45...Qe3 46.Qxd6 Re8 47.Qd7+ Re7 48.Qc6 Qxe4 49.d6 Qxf5+ 50.Kg1 Rd7 51.Qxb5 >>>> ² (0.47) Depth: 23/56 17:29:25 78776519kN, tb=3 >>>> >>>>(Irazoqui, Cadaqués 28.02.2001) >>> >>>Compare to the analysis of yace after few hours of playing against itself and >>>going back. >>> >>>1...Qe3 2.Qxd6 Re8 3.Qd7+ Re7 4.Qc6 Qxe4 5.d6 Qd3+ 6.Kg1 Re8 7.Kh2 Qxf5 8.Ra2 >>>Rd8 9.Qxb5 Rxd6 10.Qxc4+ Kg6 11.Ra7 Kh7 >>> >>>It seems that the lines are similiar and I suspect that humans did not analyze >>>this line to prove if it is a draw or not a draw. >>> >>>I did not believe that this traingle Qc6-d6-d7-c6 can be a good idea for white >>>but maybe humans are wrong and it is not a draw. >>> >>>It is clear that deeper blue could not find this idea otherwise the programmer >>>could tell the public that it is not a draw so practically kasparov could draw >>>by playing Qe3 but it does not answer the question if Qe3 is objectively a draw. >>> >>>Uri >> >>OK, fine, but obviously Qe3 is the only chance for black and Deep Fritz, Deep >>Shredder and Junior 7 beta see it very quickly. If Deep Blue was so extremely >>fast, why did it expect Qxc6 and didn't see Qe3? >> >>Enrique > >I believe that the answer is simply one of the following or both of them: > >1)Deeper blue is worse than Deep Fritz and could not see the perpetual because >it did not do the right extensions(the main line of Deep Fritz suggests that >Deep Fritz can see the perpetual after many hours so it has a main line that >avoids it) This is totally flawed reasoning. For a program to see a perpetual in its search, it must meet two conditions. The conditions are summed up in the following possibilities: 1. It finds a perpetual it can force, regardless of what the opponent does, and it believes that it is losing unless it takes the perpetual. 2. If finds a perpetual the opponent can force, regardless of what it does itself, and it believes that the opponent is losing and will choose to take the perpetual. If a program believes white is losing in this position, then it will think white is trying to repeat and black is not. If a program believes black is losing in this position, then it will think black is trying to repeat and white is not. Those two cases are vastly different. If DB believed (1) and Fritz believes (2) then comparing their results of looking for a draw is pointless. In any case, the forced (absolutely forced by black with white struggling to avoid the repetition) requires > 60 plies to see. I don't care _how_ long you give fritz, it is _not_ going to be able to find the forced draw. It is simply too deep. > >2)Deeper blue had a different evaluation and gave the line of Qe3 worse score(it >prefered to be some pawns down in opposite colour bishop endgame and not a >bishop down for 2 pawns with a chance for perpetual check) > >Uri It is a mistake to believe that a program can force a draw, just because it says 0.00... If it thinks it is winning, it will assume the opponent will go toward the draw. If the opponent is _really_ winning, and the program doesn't understand this, then it will be saying draw, but it will really be losing and not know it. I see this quite often in comp vs comp games on ICC. Before a program can intelligently choose to say "draw" it has to have some solid idea about who actually stands better in the position. They don't do this very well in many cases.
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